Triangle T(n,k) = coefficient [x^n] of x^2/(1-(k+1)*x^2-x^3) for row n, and columns k = 0..n, read by rows.
A117724
Triangle T(n,k) = coefficient [x^n] of x^2/(1-(k+1)*x^2-x^3) for row n, and columns k = 0..n, read by rows.
Terms
- a(0) =0a(1) =0a(2) =0a(3) =1a(4) =1a(5) =1a(6) =0a(7) =0a(8) =0a(9) =0a(10) =1a(11) =2a(12) =3a(13) =4a(14) =5a(15) =1a(16) =1a(17) =1a(18) =1a(19) =1a(20) =1a(21) =1a(22) =4a(23) =9a(24) =16a(25) =25a(26) =36a(27) =49a(28) =2a(29) =4
External references
- oeis: A117724